Growth inhibition by gamma rays affects lipids and fatty acids in garlic sprouts during storage
Mónica B. Pérez, Marta I. Aveldaño and Clara A. Croci
Postharvest Biology and Technology, Volume 44, Issue 2, May 2007, Pages 122-130
2007
บทคัดย่อ
Growth inhibition by gamma rays affects lipids and fatty acids in garlic sprouts during storage
Bulbs of cv. Colorado garlic were irradiated at dormancy with a dose of 60 Gy of gamma rays and stored for 8 months, during which period the content and fatty acid composition of phospholipids (PL), glycolipids (GL) and neutral lipids were analyzed on three occasions. No significant changes were observed a few hours after irradiation, but the treatment resulted in a considerable reduction in lipid and fatty acid content 150 and 240 days post-harvest, with a concomitant reduction in the process of sprout growth. In total lipid, all fatty acids including the major linoleic acid (18:2) decreased, the largest decrease being in linolenic acid (18:3). The latter was a relatively minor component of PL (phosphatidylcholine and -ethanolamine) and a major acyl group of GL (monogalactosyl- and digalactosylglycerol). Radioinhibition had the opposite effect on polyunsaturated fatty acids of PL and GL, the 18:3/18:2 ratio decreasing in the former and increasing in the latter. Accretion of lipids and fatty acids is a normal biosynthetic process accompanying sprout growth, and the long-term effects of irradiation are interpreted to reflect a delay or slowing down of such process.